#include <iostream>
using namespace std;

class A{
public:
	A (void):m_age(20) {
	} 
	void print (void) 
	{
		cout << "年龄:" << m_age <<endl; 
	}
private:
	int m_age;
};

int main (void)
{
	A a;
	a.print();
	return 0;
}

